1. Field of the Invention
This invention relates generally to foldable support structures and in particular to household step stools and/or step ladders.
2. Summary of the Prior Art
The well-recognized utility and convenience of step stools for household use is offset to a considerable degree by the lack of a suitable place for their storage in the average home. While most such stools are easily foldable, even in folded condition they occupy sufficient space, typically four to eight inches in the thickness dimension, that they either must be stored in the basement or garage, where they are not near at hand to the kitchen or other rooms in which they are most frequently needed, or they must compete with, and exclude from a convenient storage closet, other household implements (e.g., ironing board, vacuum cleaner, etc.).
Aside from the problem of storage, the desirability of minimizing the folded size of step stools has long been recognized for other reasons and considerable effort devoted to achieving compactness. Thus, for example, U.S. Pat. No. 3,059,722 points out the importance of achieving a sufficient degree of compactness to comply with carton-size limitations imposed on U.S. Parcel Post shipments and/or to avoid the necessity of packing step stools in disassembled or partially assembled form, the latter alternative being highly undesirable from the marketing standpoint.
Further examples of folding arrangements for step stools are shown in U.S. Pat. Nos. 2,952,301: 3,011,585 and 3,058,544, but in each case the effect of folding is simply to reduce the volume occupied by the structure whereas the present invention provides a construction in which folding reduces the volume occupied to a practical minimum, viz., that of the largest single structural component.
Another shortcoming of prior art step stools is that whatever compactness is achieved in folding is attained by resort to relatively complex structures, usually involving several pivotal links, with attendant loss of rigidity/stability and increases in manufacturing cost and, therefore, selling price. In contrast, the present invention contemplates a step stool which, in its two-step form, has only four relatively movable parts, two being the steps themselves, and no pivotal links, hangers, or braces.
It is, therefore, a general object of the invention to provide a novel step stool which overcomes or mitigates at least some of the problems of comparable prior art devices as discussed above.
A primary specific object is the provision of a step stool which folds to occupy a space no larger in any dimension than its largest component member.
Another object is to provide a step stool which can be stored in a very narrow space such as a single slot of a tray cupboard.
A further object is the provision of an improved step stool fulfilling the preceding objects in a structure which is susceptible of low-cost manufacture, is easily opened and closed, and provides a very stable unit when erected.